Optimising decommissioning of oil and gas pipelines with respect to the commercial fishing sector on the UK continental shelf.

石油和天然气(O&G)和商业渔业是使用英国大陆架(UKCS)的两个最大的利益相关者，特别是北海。有证据表明，渔民目前的目标是管道，这是一种鲜为人知的活动，对退役具有多个部门的影响。正如合作伙伴所确定的，挑战在于：监管机构及其顾问需要了解管道周围的商业捕捞做法，以便预测各种管道退役选择对渔业和渔业部门的影响。这样的理解将有助于确定最具成本效益、符合法律规定、安全和环境可持续的管道退役备选方案。这种方法将降低所有利益相关者的成本，并最终降低英国纳税人的成本。为了能够开采英国大陆架(UKCS)的石油和天然气(O&G)，自20世纪60年代以来已经安装了超过45,000公里的管道[1]。只有2%已经退役，而且很少有关于退役对其他行业和环境的后果的研究。许多管道的使用寿命即将结束，需要退役。与平台不同的是，管道不受OSPAR 98/3关于海上处置设施的禁令[2]的影响。管道退役是在个案的基础上，通过对备选方案的比较评估来考虑的。经营者必须证明，任何拟议的战略都符合确保航行和捕鱼安全以及保护海洋环境的国际义务[1]。在英国，捕鱼是一项重要的生态和经济活动[3]。由于O&G和渔业的重叠，两者之间不可避免地存在物理上的相互作用，包括管道对渔具的损坏[4]和渔具对管道的损坏[5]。禁止船只在平台周围500米的禁区内捕鱼[6]，但不适用于管道。船只将管道作为捕鱼场的轶事一直存在，船只被认为可能受益于将吸引到管道的鱼作为目标[7，8]。2014年，南部大西洋渔业管理系统和海洋科学服务部联合进行的分析量化了这种相互作用的程度，发现北海三分之一以上的底层捕捞鱼类发生在管道200米范围内。因此，2500条石油和天然气管道退役战略的选择将对渔业和环境产生影响。拟议的项目汇集了监管机构(环境和气候变化部)、他们的顾问(苏格兰海洋科学公司)以及渔业和O&G部门的代表(分别是苏格兰渔民联合会和英国石油和天然气)，以扩展2014年的分析(见上文)，并将其转化为对一系列现实退役方案(例如，0%-100%的管道拆除，包括带岩石的管道，取决于管道大小的拆除等)对渔业影响的预测。第一阶段将是整理关于管道属性(尺寸、保护材料、安装日期)和管道周围捕鱼行为的数据，并通过量化和描述渔民在渔场之间移动时管道经常穿越的位置，确定管道/捕鱼相互作用的“热点”。然后将确定现实的退役选择的影响。该项目的最后阶段是将这一新知识植入相关的利益攸关方社区(例如，监管者、他们的顾问和业界)。这将通过知识中介活动(例如，多部门研讨会)、通过行业出版物和直接通过项目伙伴本身实现。

The oil and gas (O&G) and commercial-fishing sectors are among the two largest stakeholders that use the UK continental shelf (UKCS), particularly the North Sea. Evidence suggests that fishermen currently target pipelines, a poorly understood activity which has multi-sector implications for decommissioning. The challenge, as identified by the partners, is: the regulator and their advisers need to understand commercial fishing practices around pipelines in order to predict the consequences of various pipeline decommissioning options to both the O&G and fishing sectors. Such an understanding will enable the identification of the most cost-effective, legislatively compliant, safe and environmentally sustainable pipeline decommissioning option. This approach will reduce costs to all stakeholders and, ultimately, the UK taxpayer. To enable exploitation of UK Continental Shelf (UKCS) oil and gas (O&G), more than 45,000 km of pipelines have been installed since the 1960s [1]. Only 2% have been decommissioned and there has been little research on the consequences of decommissioning to other industries and the environment. Many of the pipelines are reaching the end of their useful lives and need decommissioning. Unlike platforms, pipelines are not covered by the OSPAR 98/3 ban on the disposal of installations at sea [2]. Pipeline decommissioning is considered on a case-by-case basis, by comparative assessment of the options. Operators must show that any proposed strategy meets international obligations to ensure the safety of navigation and fishing, and protection of the marine environment [1]. In the UKCS, fishing is an ecologically and economically important activity[3]. Due to the overlap of the O&G and fishing industries there is inevitably physical interaction between the two, including damage to fishing gear from pipelines [4] and to pipelines from fishing gear [5]. Vessels are banned from fishing within the 500 m exclusion zone around platforms [6], but no such restrictions apply to pipelines. Anecdotal accounts of vessels targeting pipelines as fishing grounds have always existed, with vessels thought to potentially benefit by targeting fish attracted to pipelines [7,8]. In 2014, analyses jointly undertaken by SAMS and MSS quantified the extent of this interaction and found that over a third of North Sea (NS) demersal trips fish occurred within 200 m of a pipe. The choice of decommissioning strategy of the ~2500 oil and gas pipelines will therefore have implications for the fishing industry and the environment.The proposed project brings together the regulator (Department of Environment and Climate Change), their advisers (Marine Scotland Science) and representatives of the fishing and O&G sectors (Scottish Fishermen's Federation and Oil and Gas UK respectively) to extend the 2014 analysis(see above) and translate it into predictions of the impact of a range of realistic decommissioning scenarios (e.g. 0 - 100 % pipeline removal, covering pipelines with rocks, pipeline-size dependent removal etc) on the fishing industry. The first stage will be to collate data on pipeline attributes (size, protective material, date of installation) and fishing behaviour around pipelines and identify 'hotspots' of pipeline/fishing interactions by quantifying and characterising the location where pipelines are frequently crossed as fishermen move between grounds. The impact of realistic decommissioning options will then be determined. The final stage of the project is to embed this new knowledge into the relevant stakeholder community (e.g. regulators, their advisers and industry). This will be achieved via knowledge-brokering events (e.g. multi-sector workshops), via industry-publications and, directly, via the project partners themselves.